Question

In response to a low glomerular filtration rate (GFR), what role would the sympathetic nervous system have on maintaining homeostasis (hence increasing GFR back to a normal level)?

Answer 1

Sympathetic nervous system is one of the two main divisions of Autonomic nervous system.

The sympathetic nervous system is responsible for up- and down-regulating many homeostatic mechanisms in living organisms. It stimulates the body's fight or flight response.

It influences the renal regulation of arterial pressure and body fluid composition.

Sympathetic nerves also mediate changes in the urinary water and sodium excretion. This takes place by regulating the renal tubular water and sodium reabsorption throughout the nephron.

When Glomerular filtration rate (GFR) decreases, sympathetic nervous system is responsible for changes in the renal blood flow and regulates the GFR by constricting the renal vasculatures and changing the activity of the renin–angiotensin system.

Hence, sympathetic nervous system increases the renin secretion and maintains the homeostasis.